1. Field of the Invention
This invention relates to apparatus for removing foreign matter from a flowing liquid and more specifically to means for removing soil and the like from dishwashing liquid in a dishwasher apparatus.
2. Description of the Prior Art
A number of different devices have been developed for removing soil and the like from dishwashing liquid in a dishwashing apparatus. One such structure is disclosed in U.S. Letters Pat. No. 3,457,929 of Richard E. Madden. As shown therein, the dishwashing liquid is returned from the tub into a funnel-like member having a perforated upper portion. The dishwashing liquid flows outwardly through the perforations into a collecting sump for recirculation to the tub by a recirculation pump. Foreign matter in the dishwashing liquid is caught to be retained within the perforated funnel portion. Upon completion of the dishwashing operation, the drain pump connected to the lower end of the funnel is actuated so as to draw the dishwashing liquid downwardly from the funnel to carry therewith the collected soil and foreign material for disposition to drain as desired.
An early dishwasher structure is shown in U.S. Pat. No. 1,034,229 of J. E. Gribben. The bottom of the tub is provided with a channel into which dirty water and sediment may flow in the operation of the dishwasher. This waste material is drawn off periodically through a front discharge element. A plate overlies the channel to prevent washing of the sediment from the channel in the operation of the dishwasher.
Jakob Buchi shows in U.S. Pat. No. 1,431,367 a device for separating sand carried in watercourses which includes means for checking the velocity of the incoming water so as to uniformly distribute the velocity across the width of a chamber permitting settling of sand from the water in the chamber. The device includes means for drawing off the upper clean layers of the water from which the sand has been settled.
In U.S. Pat. No. 1,853,589, W. R. Walker shows a dishwashing machine having a sump portion in which the soil accumulates during the dishwashing operation. A valve controls the discharge of the dishwashing liquid from the bottom of the sump as upon completion of the dishwashing operation so as to remove the collected soil from the bottom of the sump at that time.
Remigius Pauly et al. show in U.S. Pat. No. 2,155,868 a dishwashing machine similar to the Walker machine in providing a sump wherein the soil is collected during operation of the dishwasher and from which the soil may be removed with the dishwashing liquid upon completion of the dishwashing operation.
Edward W. N. Boosey shows in U.S. Pat. No. 2,237,545 a floor drain provided with a removable basket through which drain liquid may pass. A water and oil separator is provided in the sump for further cleaning of the drained liquid.
In U.S. Pat. No. 2,575,768, Harold C. Pearsall shows a skimmer device for skimming grease and the like from a liquid such as soup or other liquid foods. The grease is collected in the device and delivered therefrom by inversion of the device.
Joseph A. Pietsch shows a dishwasher with a soil separation chamber in U.S. Pat. No. 2,700,978 having an annular sump in which soil is collected during the dishwashing operation. A drain port communicates with the sump which is opened upon completion of the washing operation to drain liquid from the tub. The drain port is at the bottom of the soil collecting space.
William R. Molnar shows a clothes washing machine in U.S. Pat. No. 2,807,949 wherein an area of low turbulence is provided under the agitator. A nozzle is provided for discharging liquid and soil particles from the area of limited turbulence during the washing operation.
In U.S. Pat. No. 3,511,415, William P. Crowe shows a water cooler having a sloping upper wall and vents connecting the upper ends of a plurality of passes to the uppermost portion of the wall at the outlet of the cooler.
John B. Anderson et al show a method and apparatus for separating suspended material from a fluid stream in U.S. Pat. No. 3,768,648. The settling means includes a plurality of inclined passages of chevron cross section to provide a high critical flow rate. Material settled out from the liquid during the liquid flow through the apparatus collects in a V-shaped groove portion thereof from which the collected material is subsequently discharged.